Viscosity measurements are known from the prior art, such as by way of measuring a pressure drop, a flow through a capillary, or by measuring a damping of an oscillation of a submerged probe. Furthermore, rotary rheometers for measuring viscosities are known. By way of measuring methods and measuring devices of this type it is indeed possible for the viscosity to be measured, occasionally even at high temperatures and high pressures; however, by way of measurements of this type it is impossible for elastic properties to be measured at a simultaneously low viscosity.